Developing tank for developing photographic films



"Sept l0. 1940-- s. FREEMAN DEVELOPING TANK FOR DEVELOPING PHOTOGRAPHIC FILNS.

Filed April 2o, 1939 s sheets-sheet 1 INVENTOR C yZ0 W f/lr ATTORNEYS sept. 1o, 1940. s, FREEMAN 2,214,581

DEVELOPING TANK FOR DEVELOPING PHOTOGRAPHIC FILMS Filed April 20, 1939 3 Sheet-.s--Sheet4 2 INVENTOR ATTORNEYS` Sept. 10, 1940. s. FREEMAN 2,214,581

DEVELOPING TANK FR DEVELOPING PHOTOGRPHIC FIIJS s sheets-sheet s Filed April 20, 1939 m R Y NVENTOR Patented sept. 1o, v1940 PATENT OFFICE DEVELOPING TANK FOR DEVELOPING PHOTOGRAPHIC FILMS Samuel Freeman, New York, N. Y.

Application April 20, 1939, Serial No. 268,883

9 Claims.

My invention relates to a new and improved cfieleveloping tank for developing photographic ms. One of the objects of the invention is to del vise a tank of.- this kind which can be loaded in daylight and a method whereby said operation can be readily performed.

Another object of the invention is to provide a device of simple and reliable construction which shall be easy to operate and which can .be manufactured at low cost.

An'other object of the invention is to provide a simple device whereby the exposed film, covered with the protective paper, can be placed l5 within a loading chamber which is located within the tank, and in which all the important operations can be performed after the cover ofthe tank has been applied and while the cover is in the closing position.

' 20 Another object of the invention is to provide a device having a separable loading member into which the lm, covered with the protective paper,

caribe placed. This loading member can then be placed in the loading chamber, and all the subsequent operations are then performed without removing the loading member from the loading chamber or loading portion of the tank.

Other objects of my invention will be set forth in the following description and drawings which illustrate certain preferred embodiments, it being understood that the above statement of theA objects of my invention is intended generally to explain the same without limiting it in any manner.

Fig. l is a top plan view of the improved device with the cover removed.

Fig. 2 is a vertical longitudinal sectional view of the device, with the cover in its operative or closing position.

Fig. 3 is an elevation, partially in section, on

the line 3--3 of Fig. 1.

Fig. 4 is a sectional view on the line 4-4 of Fig. 3.

Fig. 5 is a detail sectional viewof the shaft means on which the spools are mounted.

Fig. 6 is a sectional view on the line 6 6 of Fig. l.

Fig. 'l is a partial detail plan view of the loading member and of the closed rear end of the loading chamber or loading portion of the tank.

Fig. 8 is a top plan view of another embodiment of the guide member which is used for guiding the film from the loading member to the spools.

Fig. 9 is a rear end view of Fig. 8, 'taken' at the 56 left-hand side oi Fig. 8.

(ci. sas-90.5)

Fig. 10 is a side elevation oi.' the guide which is shown in Fig. 8. l

Fig. 11 is a sectional view, partially in elevation, corresponding to Fig. 2, and showing a different embodiment of the tank.

Fig. 12-18 are detail sectional views, partially in elevation, and illustrating the sequence of operations in utilizing the device.

The device comprises a tank I which can be y made of Bakelite or of any other suitable resin 10 or of any material. At its upper end the tank I is provided with a ledge 2. The tank is also provided with a shoulder 3, which is located inwardly of the flange or ledge 2.

As shown in Fig. 1, the ledge 2 andthe shoulder 15 3 respectively have the shape of three sides of a rectangle, save that the ledge 2 has rear transverse projections 2a. The cover 4 lits -fairly closely, but not liquid-tight, between the flange 2 and the shoulder 3. The cover 4 is provided with 20 a channel-shaped lip 5. This channel-shaped lip 5 consists of a main member which is substantially parallel to the front transverse edge of the cover 4. This main member has two relatively shortmembers which are-parallel `to the longi- 25 tudinal edges of the cover. Said main portion of the lip 5 is located behind the right-hand upstanding wall of the lip 3, referring to Fig. 2,. The right-hand-up'standing wall of the lip 3 is an upward continuation of the right-hand up- 30 standing wall of the tank I, and the cover 4 is therefore located inwardly of the flange 2, and that portion of the cover which is located at the right of the loading chamber is located between flange 2 'and lip 3. The bottom edge of cover 4 35 is indicated by a broken line in Fig. 2.

Referring to Fig. 3, the cover is provided with depending front and rear walls 4a, which are located at the left of the flange 2. As shown in Fig. 2, said cover is `also provided with a left o end-wall b. The cover therefore provides a. light-tight closure for the tank.

As shown in'Fig. 4, the front longitudinal wall of the tank I is provided with a bore or perforation 6.' The loading member 1 is also made of Bakelite or any other suitable inert material. This loading member 1 is provided with a slot 8 which is open at the rear end of said loading member and which is closed at the front end of said loading member. At thelfront of said load- 50 ing member l, it is closed by a front end-wall 9. Said front end-wall 9 is provided with an integral stud projection I0, and this is. provided with an integral reduced stud or projection I I. An annular head I2 is connected to the stud I I by suitable j member to turn counterclockwise, so as the protective paper removable fastening means. A locking arm i4 yis provided with an integral sleeve or ring I5,

which is mounted turnably upon the larger stud I0. As shown in Fig. 4, the member 9 is located turnably in the bore S of the front wall of the tank I, and said bore or opening 6 oi' said front wall is provided with a shoulder so as to limit the insertion of the loading member 1 into the tank. Since the sleeve I5 is turnable relative to the stud IIS, the locking arm i4 can be turned relative to the loading member. As shown in Fig. 7, the rear longitudinal wall of the tank I is provided with a rearwardly extending boss or enlargement It, which is closed by a rear end-wall I1.

When the loading member 1 is in its operative position, its openl rear end is located turnably in said boss or enlargement I8, whose inner wall serves as a bearing for said loading member i.

The wall of the boss I6 is provided with a bore 2I which has a reduced end-portion. A bulletshaped latch-member I8 is provided with a head 29 which iits slidably in the bore 2i. A compression spring 22 is located between the head .20 and a cap 23 which is screwed into the outer tapped end oi said bore 2I. The compression springv 22 will therefore hold the latch I3 yieldably in position and the head 20 prevents the latch I8 from beine forced out of its bore. The loading member 1 is provided with a cam recess which is aligned with the inner end of the latchmember I8 when the loading member is in the position in which it is desired to lock the protective paper relative to said holding member. In such locking position, the latch-member I2 engages the wall of said recess with sufficient force under the action of spring 22 so as to urge one of walls of slot 8 towards the rear end-Wall R of thetank, as shown in Fig. 14, for example. 'I'he spring Z22 then operates to urge the loading to clamp P firmly against the inner surface oi rear wall R oi the tank and to hold said paper firmly in position. v(Zither spring means can be used to secure this clamping eiect. However, 'oy exerting suiiicient manual turning force, the loading member can be turned from the position of Fig. 14 to that of Fig. l2. The outer wall of the loading member 1 is provided with an external ridge or rib 24. 'The iront and rear ends of said rib 24 are respectively spaced from the front end rear ends of the loading member 1. The longitudinal wall ci' the tank is provided with a notch 28, as shown in Fig. 3, through which the rib 24 is pushed when the loading member is inserted into the loading chamber of the device. When the loading memer has thus been fully inserted, the rib 2i clears the notch 25 so that the loading member 1 can then be turned clockwise or counterolockwise.

The inner surfaces oi the front and rear longitudinal walls ci thetank are provided with upstanding inwardly directed aligned iront and rear ribs it against which the rib 2d abuts, as shown in Fig. l, in the release position or the loader which is shown in 2. This is the position in which the nlm and the protective paper are unwound from the spooi which is located within the loader.

Referring 'for example to Fig. 17, when the loading member is turned counter-clockwise approximately 180 from the position shown in Fig. 2 to the position o1' Fig. 17, the rib 24 presses the protective paper P of the film against the inner surface of the rear end-wall R of the tank.

This end-wall R thus serves 'as a stop to limit the counter-clockwise .turning of the loading member from the position shown in Fig. 2. In the position of the loading member which is shown in Fig. 17, the protective papel'. P is clamped so that it cannot be moved relative to the loading member, and theloading member is held in said clamping position by spring 22.

The tank I is provided with a pair of lfilm-holding spools 21 and 21a. 'Ihese spools are identical. As shown in Fig. 2, the walls of said spools 21 and 21a which face each other, are respectively provided with spiral grooves G. The groove G of each spool 21 and 21a has an inlet end which is' close to the center of the respective spool.

Fig. 5 shows a solid rod 28 which is also made of Bakelite or other suitable material. At one end thereof, said rod 23 is provided with integral spaced heads 23 and 33. At said end, the rod 23 is provided with a tapped recess 3l. An externally threaded sleeve 32 is mounted upon the inner rod 23. One end of said sleeve 32 abuts the head 29. The washer 33 is held against the other end of the sleeve 32 by means of a clamping screw 33 whose shank is located in` a tapped recess oi' the rod 23. The head of the screw 34 servesas one of the bearings for the assembled rod 28 and sleeve 32. i

As shown in Fig. 1, the front and rear members oi the shoulder 3 are provided with vertical recesses which extend downwardly from the top wall of said shoulder 3, and in which the head of the member 34 and the head 30 are respectively turnably located.

The rod 23 and the sleeve 32 have corresponding transverse slots-3l and 35a, asv shown in Fig. 5. The inner end of a ilexible strap 36 is located and held in said slotsg35 and 38a, so that the members 23 and 32 turn in unison. Said strap 3i; is made of rubberized material, or other material which is inert to the developing and fixing solution. When members 28 and 32 are turned in unison in one direction, the strap 3S is wound spirally around the sleeve 32. The outer end of the strap 3l is provided with a clamp 31.

lifieans external to the tank are provided for turning the members 32 and 23 in unison with the holding spools 21 and 21a. As shown in Fig. l, a rod 33 which is externally threaded at its inner end, is screwed into the recess 3I'oi' the rod 28. A washer 33, made oi rubber or other suitable material, is mounted on the rod 33. A head 40 is also mounted on said rod 33 and said head I3 compresses the washer 39 so as to produce a liquid-tight joint at the iront longitudinal Wall oi' the tank. A knob il is connected to the outer end ot said rod 38. When the knob d@ is turned, it turns the members 28 and 32 in unison with the spools 21 and 21a.

As shown in Fig. 1, the outer wall of the externally threaded sleeve 32 is provided with a series o! spaced recesses 32. Each of the spools v21 and 21a has a hub I3, which is clearly shown in Figs. l and 6. Each hub 33 is provided with a latch-member 43, which is pressed inwardly by a compression spring 43, which is held in place by means of a removable threaded plug 48.

When the latch member 44 enters one of thel recesses 42, the respective spool 21 or 21a turns in unison with the members 28 or 32. The spools 21 and 21a can thus be adjusted towards or away `from each other so as'to accommodate illms oi' varying width.

The guide member l1 is provided for leading guiar arm 55a connected thereto. A series of.

the nlm from the slot 9 of the loading member 1 to the inner ends of the grooves G.

As shown in Figs. 1 and2, the guide member 41 is provided with ribs 48 which are integral with upstanding projections 49, which are integral with the left-hand edge of the guide member 41.x

The ribs 48 are angular, as shown in Fig. 1, so

that the film is led between guide member 41 land the longitudinal parallel portions of ribs 48.

Said upstanding projections 49 are provided with lugs 50 which enter vertical recesses 5i of the front and rear walls of the flange 3. Said recesses are open at their upper ends. 'Ihe guide member 41 can thus be detached from the device. It normally occupies the position shown in Fig. 2, in which it abuts the sleeves 32 or the hubs 43, depending upon the spacing between the spools 21 and 21a. The guide member 41 is turnable relative to the tank. Adjacent the sleeve 32, each of the spools 21 and 21a is pro-v vided with radial spaced arms 52, soV that the;

two members 59 and 54, having hubs through which a cylindrical rod 55 il passed. These hubs" have set screws 56 so that said hubs can be clamped adjustably on the rod 55 so as to adjust the space between said members 53 and 54.

As shown in Fig. 8, the member 53 has an anspacing members 51 are mountedon said arm 56a. Said arm 56a is provided with an enlarged head 58. The adjacent surfaces of these spacing members 51 have interfitting tongue-and-groove joints. By varying the number of spacing members 51, the effective width of the guide 41a can be adjusted.

The modified guide 41a shown in Figs. 8-10 has counter-weights 59. The ends of the member 55 are equivalent to the members 50 of Fig. 1. The counterweights 59 are sufficiently heavy to normally hold the guide 41a in a substantially horizontal position. In such position, the angle between the guide 41a and the horizontal plane is smaller than the angle between the guide 41a and the horizontal plane when the film has been fully threaded into the grooves G. Therefore, when the film has been fully threaded into the grooves G and said lm has wholly cleared the guide 41a, the counter-weights 59 slightly tilt the guide 41a towards the horizontal plane. 'I'herefore, if the spools'21 and 21a are now 'turned reversely or counterclockwise, the rear end of the film will not strike the guide 41a. A rod 80 is connected to one of the counter-weights.

When it is desired to diminish the width of the guide 41a, in the embodiment of Fi8s.810, one ormore of the spacing elements 51 can be turned reversely on the arm 58a, to restupon the arm 59.

The embodiment shown in Fig. l1 isA substantially 4the same as that shown in Fig. 1,l save that in Fig. l1 the loading chamber has a. bottom convexo-concave all 82 upon which-the loader 1 rests turnably. In the embodiment of' Fig.f11, as in Fig. l. bearings are provided for the loader 1 in the front and rear longitudinal walls of the tank l.

The tank is provided with a lip L by means of which liquid can be poured out oi said tank.

The method of using the device is as follows:

The cover 4 is removed and the strap 35 is pulled out to its maximum extent and it is led over the right-hand end-wall of the tank. A suitable quantity of developing solution is then poured into the tank. Ordinarily it is sufficient to fili the tank to about one-half its height.

The roll of film is of the usual type. This includes the usual film F, to whose front end a short pull-strip of paper P is connected in the well-known manner. This is usually done by adhesive. `In addition, the roll 'of film is provided with the usual long strip of protective paper P, which, together with the film F, if wound spirally around the shank of the spool 1i. 'I'he strip of paper P is longer thanthe film and it is connected to the rear end of the film by means of a short strip of cloth 10. This strip of cloth is connected to the rear end of the film F and to the protective paper P, by means of suitable adhesive. f-

While the cover is detached from the tank, the loader iis removed and the roll of film is placed into the loader, through its open rear end. The loader is now placed in the position shown in Fig'. 12. The front end of the paper strip P is now pulled so as to turn the roll of film. 'I'his strip of protective paper P is led towards the lefthand or rear end-wall R.. After a sufiicient length of the paper P has been unrolled, the paper strip P is exposed, as shown in Fig. 13. The paper strip P is led in a direction reverse to the direction of the strip P. 'I'his can be done by placing a pencil or other suitable instrument upon that part of the paper P which is still in vtheV rolled-up condition, so that the strips P and P' are respectively led in opposite directions.

As soon as the paper strip P has been exposed and before any part of the film has been exposed to the light,A the loader 1 is turned counterclockwise to the position shown in Fig. 14 from the 'position shown in Fig. 1,2, so as to shut oifthe light from the film, even though the cover 4 is off the tank. The clamp 31 is now connected to the pull strip P'. The belt 36 now overlies the guide 41 with part of said belt 36 convtacting with the guide41. The cover 4 is now replaced and locked so as to shut off light from the film.

The loader 'l is then turned to the position shown in Fig. l5, this being the same as the positions shown in Figs. 12 and 13. The knob 49 is now turned so as to turn the spools 21 and 21a. thus winding up the strap 36 around the sleeve 92 and leading the film into the grooves G of the holding spools 21 and 21a.

At the same time the paper P is pulled away from the left-hand end-Wall R of the tank so that the paper P is continuously separated from the film as the film is led into the grooves G. As shown in Fig. 15, when the cover 4 is placed upon the tank, the free end of the protective paper P projects to the left of the cover. While the strip of paper P can be removed and the clamp 91'can directly grip the end of the film, it is preferable to retain the strip P. As the film is collected in the grooves G, the angle between the guide 41 and the horizontal plane is'diminished. When the connecting cloth strip 1li is moved into the position shown in Fig. 16, thus clearing the loader the operator feels an increase in the tension. The operator then moves the 'loader to the position shown 'in Fig. 17 so that the loader clamps a part of the paper P against the Wall R Aof the tank, leaving the cloth strip 10 perfectly free. vSuilicient pull is exerted upon thestrip Pl so as to separate the same from the cloth strip 10, while the member 4U is turned simultaneously to continue the winding-up of the film in the grooves G. The adhesion between the cloth strip 10 and the film F is greater than the adhesion between the cloth strip 10 and the paper strip P, so that the cloth strip /10 remains adhering to the ilm F. Y

After the strip P has been separated from the strip 1G, the loader is moved back to the position shown in Fig. 18 and the paper strip P is completely removed from the apparatus and the nlm F is located wholly in the grooves G. The loader is then turned counterclockwise to the position shown in Fig. 14, so that when developing, none of the developer will get into the loader l. The counter-weights 5S tilt the guide I11a so as to diminish the angle betweensaid'guide and the horizontal plane. The latch I8 and the spring 2E have sufficient force to keep the loader rmly in the respective positions shown in Fig. ll and in other iigures.

The locking device for the cover is shown in the inoperative position in full lines in Fig. 3 and in the operative position in broken lines in Fig. 3.

The cover t is provided With a boss which is engaged by the arm i4, when this is in the broken-line position shown in Fig. 3. In said locking position the arm i4 abuts a stop 8|. After the lm has thus been wholly taken up by the spools 21 and 21a, the spools 21 can be turned back-'and-forth by operating the knob Il so as to agitata the developing solution and to develop the iilm thoroughly. The developing solution is then poured out without removing the cover l. using the lip L. Water is then poured into the tank and the film is then agitated until it has been thoroughlyy washed.

The Wash water is then poured out through the lip L, the nlm being held in' position in the grooves G. Fixing solution is then poured into the tank and the lm is agitated until the xing operation has been completed. The cover is now removed and the xing solution poured out. After the lm has been xed, the cover can be removed, and the film can be readily removed from spools 21 and 21a.

It will be noted that the guide is wholly free from the spools or discs 2.1 and 21a, and that no part of said guide engages the grooves of the members 21 and 21a. Itwill also be noted that the device has a single loading chamber.

While I prefer to use a turnable loading device, the invention is not limited to the use of a loading device which is turnably mounted in the tank. Likewise I prefer to use the clamping means illustrated herein but I can use any other type` of clamping means for preventing lm from accidentally unrolling, when the clamp member 31 is connected to the pull-stripP'. For example the clamping means can be mounted on the loader itself. Likewise by careful manipulation, it is unnecessary to hold the pull-strip P' against moving when the clamp 31 is connected thereto. The principal feature of the invention is that a single loading chamber is utilized and the clamp is connected to the pull-strip while the lm and the protective strip P are wound spirally on the shankV o! the spool 1|.

In utilizing the device. the spools or nlm takeup means 21 and 21a are oversised. so that when the nlm is located wholly in grooves G, the top of theillm in said grooves is located at a level which is below the level of the pivot of the guide 41 or 41a. Hence. when the film has fully cleared guide 41a, its counterweights'zturn the guide 41a upwardly, so that said guide `lla wholly clears the iilm in grooves G.

The width of the guide between the inner walls of members 49, is slightly less than the width of the nlm, so that the cross-section o! the film is concavo-convex when the illm is fed into grooves G. 'I'he film straightens, due to its elasticity, as it is fed into grooves G.

The space between cover 4 and wall R may be designated as means for feeding the strip P out of the tank. Other outlet means may be substituted. Y

A cover which is hinged to the tank is equivalent to a removable cover, within the scope of the claims.

The wall R may be designated as means for closing the slit in the loading device when said loading device is in predetermined position. The members l 8 and 22 are resilient means adapted to hoid said loading member releasably in said predetermined position.

One of the important features per se of the invention is that, in the embodiment of Figs. 8-10, the counter-Weights tilt the guide upwardly when all the fllm has been taken up by the spools, and this feature can be used with a guide of any type, adjustable or non-adiustable, and without the spacers of Figs. 8-10.

I claim:

l. In a daylight-loading device, a development tank which has a top edge-wall and a removable cover at said top edge-wall, the sub-combination of a loading device, said tank having means located below its top edge-wall and constructed to hold said loading device turnably in position below said top edge-wall, said loading device being shaped to hold thereon a spool on which a roll of film and a protective strip of paper are jointly wound splrally, said loading device having a slit in its wall through which said protective strip and said lm can be jointly led and unwound from said spool, film take-up means turnably mounted in said tank, ilrst means adapted to feed the iilm away from said slit to said take-up means, second means adapted to lead the paper strip out of the tank and between said top edgewall of the tank and said cover, when the cover is in operative position, said slit being sufiiciently narrow to retain the spool within said loading device, said loading device having an opening other than said slit through which the spool and the roll of film and protective paper can be inserted into said loading device, said cover being removable independently of said loading device.

2. A daylight-loading developing tank having a. removable cover, a loading member insel-table into said tank and removable therefrom, said loading member being located below said cover when it is inserted into the tank, said tank having means constructed to hold the loading member turnably when the loading member is inserted into Asaid tank, said loading member having a slit in its wall through which a lm can be fed, lm take-up means turnably located in said tank, a pull device connected to said take-up means and constructed to pull nlm away from said slit towards said take-up means, operating means externa! to said tank and constructed to operate said take-up means and said pull device in unison, the interior o! said tank having means adapted to close the slit in said loading device when the loading device is turned to apredetermined position. said loading device having an outer end-wall.

.sub-combination of a loading member which is insertable into said tank and which is removable from said tank, said tank having means to turnably support said loading member when the loading member is inserted into said tank. said load-v .ing member having a slit in its wall through which the nlm can be led, said tank having additional means located therein and adapted to close said slit when the loading member is turned in a predetermined position. said tank `having resilient means adapted to `hold said loading member releasably in said predetermined position.v

5. In a daylight-loading developing tank, the sub-combination of a loading member which is insertable into said tank and which is removable from said tank. said tank having means to turnably support said loading member when the loading member is inserted into said tank, said loading member having a slit in its wall through which the nlm can be led, said tank having additional means located therein and adapted to close said slit when the loading member is turned to a predetermined position, said additional means and said loading member being constructed to clamp an intermediate strip.

6. In a daylight-loading developing tank which has a removable cover, the sub-combination of means adapted to support a nlm within the tank. movable nlm ltake-up means located within the tank, a pull device constructed to pull nlm towards said take-up means, said pull device and said take-up means having operating means which are located external to the tank. said nlm take-up means comprising a pair of turnable members having spiral grooves whose inlet ends are located adjacent the axis of rotation oi' said turnable members. a nlm guide turnably mounted msaid tank and shapedtoleadtnemmwwards said grooves, means adapted to hold said guide yieldingly in a position in which its edge is located above the top oi the nlm which is located in said grooves.

7. For use in a daylight-loading developing tank, a guide having means constructed to connect the same turnably to the tank, said guide includinga pair of laterally adjustable main members and intermediate spacing members, said spacing members being turnably connected to one of said main members so that one or more selected spacing members can be turned out 0i' operative position, said main members being movable -towards each other and away from each other.

8. For use in a. daylight-loading developing tank, a guide having means constructed to connect the same turnably to the tank, said guide including a pair of laterally adjustable main members and intermediate spacing members. said spacing members being turnably connected to one of said main members so that one or more selected spacing members can be turned out of operative position, said main members being movable towards each other and away from each other, one of said main members being supplemental means adapted to hold the spacing members in their inoperative positions. v

9. A daylight-loading developing tank having a removable cover, a loading member insertable into Isaid tank and removable therefrom, said tank having means adapted to turnably support said loading member when the loading member is inserted into said tank, said loading member having a slit in its wall through which a nlm can be led, said tank also having turnable nlm takeup means, said tank having nrst stop-means adapted to hold said holding member in a nrst position in which its slit is located operatively relative to said take-up means, said tank having second stop-means constructed to limit the turning movement of the holding member away from said position to a second predetermined position, said tank having closure means constructed to close said slit when the holding member is in the second predetermined position.

SAMUELFREEMAN. 

